Many compositions have been in commercial use for protecting trees and shrubs. The paste type which has to be put on the plant by means of a spatula or brush is time-consuming to apply, may be washed away over time and has other disadvantages. For example, coating thickness will vary so that results are inconsistent. Moreover, paste compositions do not usually have reliable light-reflecting properties for protecting the plant from what is known as sun scald. The present invention is concerned with the provision of a protective wrap in sheet form to be supplied either as cut sheets or in rolls which can be wrapped onto a plant, e.g. around a stem or trunk, or otherwise applied to the surface of the plant.
U.S. Pat. No. 4,766,695 describes a tape for banding trees which comprises a film such as polyethylene coated with an elastomeric adhesive on one side. On the other side is a separate coating which is toxic to insects. One objective of the present invention is to provide a protective wrap in sheet form wherein all active constituents are contained in a single pressure-sensitive, i.e. tacky, coating which bonds the wrap to the plant and also contains a biolgically active protective composition such a deer, rodent or insect repellant.
It has been proposed, for example in European patent application 0 367 140 A2, to disperse a repellant, e.g., a flea repellant, in a water insoluble copolymer such as ethylene/vinyl acetate copolymer for making a dog collar in which the copolymer serves both as a carrier for an insect repellant and a sheet of material which forms the collar. By contrast, it is an object of the present invention to employ a strong, flexible backing in sheet form to provide structural strength and to give the protective wrap its shape, allowing it to be supplied in a sheet or roll form together with a separate hydrophilic matrix which serves as a reservoir for a biologically active protective composition.
A tree wrap has been available in sheet form with a sticky gum-based adhesive on one surface for bonding the wrap to the plant. While useful for preventing sun scald, no biologically active protective composition was present. As a result, the tape afforded no protection against deer, rodents, insects and other pests. Therefore, it is a general objective of the invention to furnish a protective wrap for plants which can be provided either as cut sheets or in the form of a roll in which a biologically active protective agency is molecularly dispersed within a flexible hydrophilic layer applied to a tape backing and adapted to swell upon being exposed to atmospheric moisture for releasing the protective agency into the environment to thereby provide controlled release for the protective agency, either onto the surface of the plant or onto the outside surface of the tape.
These and other more detailed and specific objects of the invention will be apparent in view of the following specification which illustrates by way of example but a few of the various forms of the present invention that will be apparent to those skilled in the art within the scope of the appended claims.